Mesopore molecular sieve and process for the production thereof

ABSTRACT

A mesopore molecular sieve having a hydrocarbon group bonded directly to a silicon atom in the metal oxide skeleton constituting the molecular sieve, wherein the content of said hydrocarbon group is from 0.01 to 0.6 mol per mol of the metal oxide. Also disclosed is a process for producing a mesopore molecular sieve having a hydrocarbon atom bonded to a silicon atom in the molecular sieve skeleton, which comprises synthesizing the mesopore molecular sieve, in the presence of a template, from: a silane compound represented by the following formula (1): 
     
       
         R n SiX (4−n)   (1) 
       
     
     wherein R represents a hydrocarbon group selected from C 1-16  hydrocarbon groups and hydrocarbon groups substituted with an N—, O-, S-, P- or halogen-containing group; n represents 1, 2 or 3; and X is selected from C 1-6  alkoxy groups, aryloxy groups, a hydroxyl group and halogen atoms and a plurality of X may be the same or different; and a metal oxide and/or a precursor thereof. According to this process for producing a mesopore molecular sieve, a mesopore molecular sieve can be readily synthesized in one stage and, in addition, a mesopore molecular sieve having an excellent performance as an acid catalyst or oxidation catalyst can be obtained because the kind and amount of the hydrocarbon group can be easily adjusted.

This application is the national phase under 35 U.S.C. §371 of prior PCTInternational Application No. PCT/JP97/01933 which has an Internationalfiling date of Jun. 6, 1997 which designated the United States ofAmerica.

TECHNICAL FEILD

The present invention relates to a mesopore molecular sieve and aproduction process thereof.

BACKGROUND ART

A mesopore molecular sieve is a new material which is expected, as aninorganic porous substance having a uniform pore size in a mesoporeregion, to be used in wide applications such as catalysts andadsorbents. U.S. Pat. Nos. 5,098,684, 5,102,643 and 5,108,725 andJP-W-A-5-503499 (the term “JP-W-A” as used herein means a “publishedJapanese national stage of international application”) disclose aprocess for synthesizing a mesopore molecular sieve by using, as atemplate, a quaternary ammonium salt or phosphonium salt having along-chain alkyl group and conducting hydrothermal synthesis.

JP-A-4-238810 (the term “JP-A” as used herein means an “unexaminedpublished Japanese patent application”) discloses a process forsynthesizing a mesopore molecular sieve by treating a layered silicawith a long-chain alkyl ammonium cation in accordance with an ionexchange method.

JP-A 5-254827 discloses a process for modifying a synthesized mesoporemolecular sieve, which comprises treating the sieve with an alkylsilanecoupling agent having a methyl group, etc. reactions with a silanolgroup etc. which exists on the surface of the mesopore skeleton, therebyadding an alkylailyl group to control the pore size or adding atrimethylailyl group to modify the surface.

An object of the present invention is to provide a novel mesoporemolecular sieve which has a hydrocarbon group bonded directly to asilicon atom constituting the skeleton of the molecular sieve and aproduction process thereof.

DISCLOSURE OF THE INVENTION

In one aspect of the present invention, the present invention relates toa mesopore molecular sieve having a hydrocarbon group bonded directly toa silicon atom in the metal oxide skeleton constituting the molecularsieve, wherein the content of said hydrocarbon group is from 0.01 to 0.6mol per mol of the metal oxide. In another aspect, the present inventionrelates to a process for producing a mesopore molecular sieve having ahydrocarbon atom bonded to a silicon atom in the molecular sieveskeleton, which comprises synthesizing the mesopore molecular sieve, inthe presence of a template, from:

a silane compound represented by the following formula (1):

R_(n)SiX_((4−n))  (1)

wherein R represents a hydrocarbon group selected from C₁₋₆ hydrocarbongroups and hydrocarbon groups substituted with an N-, O-, S-, P- orhalogen-containing group; n represents 1, 2 or 3; and X is selected fromC₁₋₆ alkoxy groups, aryloxy groups, a hydroxyl group and halogen atomsand a plurality of X may be the same or different; and

a metal oxide and/or a precursor thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an X-ray diffraction pattern of the methyl-containingmesopore molecular sieve synthesized in Example 1.

FIG. 2 illustrates a pore distribution of the methyl-containing mesoporemolecular sieve synthesized in Example 1.

FIG. 3 illustrates an infrared absorption spectrum of themethyl-containing mesopore molecular sieve synthesized in Example 1.

FIG. 4 illustrates a differential thermal analysis chart of themethyl-containing mesopore molecular sieve synthesized in Example 1.

BEST MODES FOR CARRYING OUT THE INVENTION

The present invention is described in detail below.

The term “mesopore molecular sieve” as used herein means a mesoporemolecular sieve which is a porous substance having a uniform pore sizeof 1.5 to 10 nm in the mesopore region and has a hydrocarbon groupbonded directly to a silicon atom in the metal oxide constituting theskeleton.

The silane compound for use in the present invention is one representedby the above-described formula (1), wherein examples of the hydrocarbongroup represented by R include C₁₋₆ hydrocarbon groups or hydrocarbongroups substituted with an N-, O-, S-, P- or halogen-containing group.

Specific examples of the hydrocarbon group include saturated orunsaturated C₁₋₆ hydrocarbon groups and C₁₋₁₆ hydrocarbon groupssubstituted with an N-, O-, S-, P- or halogen-containing group. Examplesof the substituted hydrocarbon group include heterocyclic hydrocarbongroups each of which contains any one hetero atom of N, O, S and P, andsaturated or unsaturated hydrocarbon groups each substituted with agroup such as —OH, —SH, —OR′, —SR′, —COOR′, —OCOR′, —NO₂, —SO2, —SO₃Hand —PO(OH)₂, a halogen atom or the like. In the above formula, R′represents a saturated or unsaturated hydrocarbon group.

Specific examples include linear alkyl groups such as methyl, ethyl,propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl,dodecyl, tridecyl, tetradecyl, pentadecyl and hexadecyl; cyclichydrocarbon groups such as cyclohexyl and cyclooctyl; unsaturatedaliphatic hydrocarbon groups such as vinyl, propenyl, butenyl, pentenyl,hexenyl, heptenyl, octenyl, nonenyl, decenyl, undecenyl, dodecenyl,tridecenyl, tetradecenyl, pentadecenyl and hexadecenyl; cycloolefin suchas cyclopentenyl, cyclopentadienyl, cyclohexenyl, cyclohexadienyl andcyclooctadienyl; cyclic ring-subsbtituted alkyl groups; alkyl groupssubstituted with an aryl or aromatic group such as phenyl, tolyl, xylyl,naphthyl and methylnaphthyl; and the above-exemplified groupssubstituted with a halogen atom such as perfluoroalkyl group,hydrofluoroalkyl group and chloro-sustituted alkyl group, morespecifically, 3-chloropropyl group, trifluoropropyl group,pentafluorobutyl group, heptafluoropentyl group andheptadecafluorotetrahydrodecyl group.

The substituent represented by X is selected from C₁₋₆ alkoxy groups,aryloxy groups, a hydroxyl group and halogen atoms, and if there exist aplurality of X, they may be the same or different. Examples of thealkoxy group include alkoxy and phenbxy groups such as methoxy, ethoxy,propoxy, butoxy, pentyloxy and hexyloxy, of which the methoxy and ethoxyare preferred.

n stands for an integer of 1 to 3. For example, when n stands for 1, thesilane compound is a trialkoxyalkylsilane, when n stands for 2, thesilane compound is a dialkoxydialkylsilane, and when n stands for 3, thesilane compound is a monoalkoxytrialkylsilane. Among them, n preferablystands for 1, because in this case, the silane compound is more firmlyincorporated in the skeleton.

Preferred examples of the silane compound include those represented bythe following formula (2):

wherein:

R: a hydrocarbon group selected from C₁₋₁₆ hydrocarbon groups andhydrocarbon groups substituted with an N-, O-, S-, P- orhalogen-containing group,

X¹, X², X³ each selected from C₁₋₆ alkoxy groups, aryloxy groups, ahydroxyl group and halogen atoms. Specific examples of the compoundrepresented by formula (2) include monoalkyltrialkoxysilane andmonoaryltrialkoxysilane.

As the template for synthesizing a mesopore substance, any knownsurfactants employed for the synthesis of a mesopore substance, such aslong-chain quaternary ammonium salts, long-chain alkylamine N-oxides,long-chain sulfonates, polyethylene glycol alkyl ethers and polyethyleneglycol fatty acid esters can be employed.

The term “metal oxide and/or precursor thereof” as used herein means asimple substance of silicon oxide or a complex between silicon oxide andan oxide of the metals exemplified below and/or a precursor thereof.

Examples of the metal species other than silicon include alkaline earthmetal elements such as magnesium and calcium and zinc, belonging toGroup II; boron, aluminum, gallium, yttrium and rare earth elements,belonging to Group III; titanium, zirconium, germanium and tin,belonging to Group IV; phosphorus and vanadium, belonging to Group V;chromium, molybdenum and tungsten, belonging to Group VI; manganese andrhenium, belonging to Group VII; iron, cobalt, nickel and noble metalelements e.g. ruthenium, rhodium, palladium and platinum, belonging toGroup VIII. Among them, boron, aluminum, rare earth elements, titaniumand vanadium are preferred.

The atomic ratio (Si/M) of a silicon atom to such a metal element (M) is5 or higher, preferably 10 or higher.

Examples of the precursor of the above-described metal oxide includeinorganic salts such as nitrate, sulfate and hydrochloride; carboxylatessuch as acetate, propionate and naphthenate; organic ammonium metalsalts such as quaternary alkyl ammonium; and metal compounds such asalkoxides and hydroxides, each with the above-described metal. Amongthem, the metal alkoxides are used desirably.

Examples of the silicon oxide or precursor thereof includetetraalkoxysilane comprising methoxy, ethoxy, propoxy or the like,silica powder, aqueous glass and colloidal silica.

In the synthesis process of the present invention, at least one ofwater, alcohol and diol is usually employed as a solvent, of which anaqueous solvent containing water Is preferred.

In addition, as in the known process, it is possible to add auxiliaryorganics to change the pore size. Examplep thereof include C₆₋₂₀aromatic hydrocarbons, C₅₋₂₀ alicyclic hydrocarbons, and C₃₋₁₆ aliphatichydrocarbons, and the above-described hydrocarbons substituted withamine or halogen, such as dodecane, hexadecane, cyclododecane,trimethylbenzene and triethylbenzene.

In the reaction mixture comprising the source of silica (including theabove-described silane compound), source of the other metal oxide,template and solvent, the molar ratio of the above-described silanecompound/(metal oxide and/or precursor thereof) is 0.01 to 0.6,preferably 0.02 to 0.50, more preferably 0.05 to 0.40, the atomic ratioof silicon/metal element is at least 5, preferably at least 10, themolar ratio of silica/template is 1 to 30, preferably 1 to 10 and themolar ratio of the solvent/template is 1 to 1000, preferably 5 to 500.

When the metal oxide or precursor thereof, template or the like is acombination of two or more substances, the above molar ratio iscalculated with an average molar molecular weight thereof.

The synthesis according to the process of the present invention iscarried out under the conditions of a reaction temperature of from roomtemperature (20° C.) to 180° C., preferably from room temperature to100° C., and reaction time of from 5 to 100 hours, preferably from 10 to50 hours.

The reaction product is usually separated by filtration, washedsufficiently with water, dried and then subjected to a removing step toremove the template contained therein, for example, by extraction withan organic solvent such as alcohol, whereby a mesopore molecular sievehaving a carbon-silicon bond can be obtained.

The mesopore substance containing a carbon-silicon bond, which substancehas been synthesized according to the process of the present invention,can be treated with an ordinarily employed surface treating agent, forexample, a silane coupling agent such as tetraalkoxysilane,monoalkyltolylalkoxysilane, dialkyldialkoxysilane ortrialkylalkoxysilane, or an alkoxide of aluminum or boron, to modify thesurface or regulate the pore size.

The mesopore molecular sieve according to the present invention has asubstituent-containing hydrocarbon group bonded directly to a siliconatom in the metal oxide skeleton constituting the molecular sieve andthe hydrocarbon group exists in an amount of 0.01 to 0.6 mol per mol ofsaid metal oxide. The meeopore molecular sieve has following features.

Specifically, the mesopore molecular sieve according to the presentinvention has features that the hydrophobic property thereof can beeasily controlled by adjusting the kind or amount of the hydrocarbongroup and a hydrocarbon-containing catalytically active component can beincorporated.

The mesopore molecular sieve of the present invention can be used in awide range of applications such as catalysts and adsorbents. Forexample, those having, in the mesopore skeleton, a catalytically activecomponent having an acid function or an oxidation or reduction function,or those having a catalytically active component such as transitionmetal component carried thereon by an ion exchange or impregnationmethod, are useful as a catalyst having a hydrophobic reaction site. Inaddition, the mesopore molecular sieve can be used as a catalyticcarrier which makes use of the hydrocarbon group bonded to a siliconatom in order to stabilize a homogeneous catalyst such as an organicmetal complex, as a controlled hydrophobic adsorbent for the adsorptionof various organic compounds, or for the controlled adsorption of watercontent such as a moisture conditioning material.

The present invention will be described in more detail with reference tothe following Examples, but the invention is not limited thereto.

In examples, the X-ray diffraction pattern was measured using “TypeRAD3” manufactured by Rigaku Denki, while the specific surface area andpore size distribution were measured by “Sorptomatic 1800” manufacturedby Carlo Erba and a peak size of differential distribution determined bythe BET and BJH methods using nitrogen was indicated as a pore size. Theinfrared absorption spectrum was measured by “Spectrometer Type 1600”manufactured by Perkin Elmer. The thermal analysis was carried out at aheating rate of 15° C./min using thermal analyzers “TGA-50” and “DTA-50”manufactured by Shimadzu Corporation.

EXAMPLE 1

In a 500-ml beaker, 80 g of ethanol and 10 g of dodecylamine were addedto 100 g of distilled water to dissolve the former in the latter. Understirring, 27.4 g of tetraethyl orthosilicate and 11.8 g ofmethyltriethoxysilane were added and after stirring for 30 minutes, themixture in the form of a slurry was obtained. The mixture was allowed tostand at 30° C. for 20 hours and reacted. The reaction mixture wasfiltered, washed with water and then dried at 110° C. for 5 hours,whereby 15.5 g of the product was obtained as white powder. In order toremove the template (amine) from the dried product to obtain a mesoporesubstance, a 5 g portion of the dried product was dispersed in 750 ml ofethanol, followed by extraction at 60° C. for one hour and thenfiltration. This extraction and filtration procedure was repeated andcarried out three times in total. The filtrate was washed with alcoholand then dried at 100° C. for 3 hours, whereby 3.4 g of amethyl-containing silica mesopore molecular sieve was obtained. Theresulting powder exhibited water repellency and when added to water, itfloated on the surface of the water.

The X-ray diffraction pattern of the resulting powder showed a strongpeak at a d value of 32.5 Å (angstrom) (see FIG. 1).

As a result of measuring the specific surface area and pore sizedistribution by the nitrogen adsorption and desorption method, it wasfound that the specific surface area was 1000 m²/g and pore size was 2.1nm (see FIG. 2).

As a result of measuring infrared absorption spectrum, an absorptionpeak attributable to deformation vibration of a CH₃—Si group was foundat around 1270 cm⁻¹ (see FIG. 3).

As a result of differential thermal analysis (measured at a heating rateof 15° C./min in the air), weight reduction and exotherm peak were foundat around 620° C. (see FIG. 4).

EXAMPLE 2

In the same manner as in Example 1, except that the amounts oftetraethyl orthosilicate and methyltriethoxysilane were changed to 33.2g and 7.2 g, respectively, 17.1 g of a dried product was obtained. A 5 gportion of this dried sample was subjected to extraction treatment inthe same manner as in Example 1, whereby 3.5 g of a methyl-containingsilica mesopore substance was obtained.

The powder X-ray diffraction pattern of the extracted sample showed astrong peak at a d value of 3.28 Å.

As a result of measuring the specific surface area and pore sizedistribution of the sample by the nitrogen adsorption and desorptionmethod, it was found that the specific surface area was 1100 m²/g andpore size was 2.4 nm. When calcined at 550° C., the sample did notexhibit water repellency, its powder X-ray diffraction peak showed adecreasing tendency with a d value of 31.4 Å, and its pore size showed adecreasing tendency to 2.1 nm.

EXAMPLE 3

In the same manner as in Example 1, except that the amounts oftetraethyl orthosilicate and methyltriethoxysilane were changed to 37.3g and 3.6 g, respectively, 17.8 g of a dried product was obtained. A 5 gportion of the dried sample was subjected to extraction treatment in thesame manner as in Example 1, whereby 3.4 g of a methyl-containing silicamesopore molecular sieve was obtained.

The powder X-ray diffraction pattern of the extracted sample exhibited astrong peak at a d value of 33.5 Å.

As a result of measuring the specific surface are and pore sizedistribution of the sample by the nitrogen adsorption and desorptionmethod, it was found that the specific surface area was 1040 m²/g andthe pore size was 2.5 nm.

EXAMPLE 4

In the same manner as in Example 1, except that 10 g of decylamine wasused as a template instead of dodecylamine, 16.4 g of white powder wasobtained. From a 5 g portion of the white powder, the template wasremoved in the same manner as in Example 1, whereby 3.5 g of amethyl-containing silica mesopore molecular sieve was obtained.

The powder X-ray diffraction pattern of the product exhibited a strongpeak at a d value of 29.6 Å.

As a result of measuring the specific surface are and pore sizedistribution of the product by the nitrogen adsorption and desorptionmethod, it was found that the specific surface area was 1020 m²/g andthe pore size was 1.9 nm.

EXAMPLE 5

In the same manner as in Example 1, except that 11.6 g oftetradecylamine was used as a template instead of dodecylamine, 15.0 gof white powder was obtained. From a 5 g portion of the white powder,the template was removed in the same manner as in Example 1, whereby 3.8g of a methyl-containing silica mesopore molecular sieve was obtained.

The powder X-ray diffraction pattern of the product exhibited a strongpeak at a d value of 34.0 Å.

As a result of measuring the specific surface area and pore sizedistribution of the product by the nitrogen adsorption and desorptionmethod, it was found that the specific surface area was 970 m²/g and thepore size was 2.1 nm.

EXAMPLE 6

In the same manner as in Example 1, except that 13.0 g of hexadecylaminewas used as a template instead of dodecylamine and that the amount ofethanol was changed to 90 ml, 17.1 g of white powder was obtained. Froma 5 g portion of the white powder, the template was removed in the samemanner as in Example 1, whereby 3.3 g of a methyl-containing silicamesopore molecular sieve was obtained.

The powder X-ray diffraction pattern of the product exhibited a strongpeak at a d value of 36.7 Å.

As a result of measuring the specific surface are and pore sizedistribution by the nitrogen adsorption and desorption method, it wasfound that the specific surface area was 980 m²/g and the pore size was2.3 nm.

EXAMPLE 7

In the same manner as in Example 2, except that 7.6 g ofethyltriethoxysilane was used instead of methyltriethoxysilane, 17.5 gof a dried product was obtained. A 10 g portion of the product wasextracted in the same manner as in Example 2, whereby 6.7 g of whitepowder was obtained. The resulting powder exhibited water repellency andwhen suspended in water, it floated on the surface of the water.

The powder X-ray diffraction pattern of the product exhibited a strongpeak at a d value of 32.9 Å.

An a result of measuring the specific surface are and pore sizedistribution by the nitrogen adsorption and desorption method, it wasfound that the specific surface area was 1050 m²/g and the pore size was2.2 nm.

EXAMPLE 8

In the same manner as in Example 2, except that 9.6 g ofn-octyltriethoxysilane was used instead of methyltriethoxysilane, 20.6 gof a dried product was obtained. A 10 g portion of the product wasextracted in the same manner as in Example 2, whereby 6.2 g of whitepowder was obtained. The resulting powder exhibited water repellency andwhen added to water, it floated on the surface of the water.

The powder X-ray diffraction pattern of the product exhibited a strongpeak at a d value of 35.3 Å.

As a result of measuring the specific surface are and pore sizedistribution by the nitrogen adsorption and desorption method, it wasfound that the specific surface area was 990 m²/g and the pore size was2.2 nm.

EXAMPLE 9

In the same manner as in Example 2, except that 9.6 g ofphenyltriethoxysilane was used instead of methyltriethoxysilane, 19.2 gof a dried product was obtained. A 10 g portion of the product wasextracted in the same manner as in Example 2, whereby 6.5 g of whitepowder was obtained. The resulting powder exhibited water repellency andwhen added to water, it floated on the surface of the water.

The powder X-ray diffraction pattern of the product exhibited a strongpeak at a d value of 32.5 Å.

As a result of measuring the specific surface are and pore sizedistribution by the nitrogen adsorption and desorption method, it wasfound that the specific surface area was 1000 m²/g and the pore size was2.2 nm.

As a result of measuring infrared absorption spectrum, absorption peaksattributable to a phenyl-silicon bond were observed at around 1430 cm⁻¹and 1130 cm⁻¹.

EXAMPLE 10

In the same manner as in Example 2, in a 1000-ml beaker, 240 g ofethanol and 30 g of dodecylamine were added to 300 g of distilled waterto dissolve the former in the latter. Under stirring, 99.6 g oftetraethyl orthosilicate and 21.6 g of methyltriethoxysilane were added,followed by the addition of 8.2 g of aluminum isopropoxide. Afterstirring for about 30 minutes, the mixture in the form of a slurry wasobtained. The mixture was allowed to stand at 30° C. for 22 hours andreacted. The reaction mixture was filtered, washed with water and thendried at 110° C. for 5 hours, whereby 58 g of the product was obtainedas white powder. In order to remove the template (amine) from the driedproduct to obtain a mesopore substance, a 5 g portion of the driedproduct was dispersed in 750 ml of a hydrochloric-acid-acidic ethanol(solution containing a 0.1 mol-HCl/l). The dispersion was extracted at60° C. for one hour, followed by filtration. This template-removingprocedure was repeated twice, in addition. The filtrate was washed withalcohol and then dried at 100° C. for 3 hours, whereby 3.1 g of amethyl-containing silica.alumina mesopore molecular sieve was obtained.The powder thus obtained exhibited water repellency and when added towater, it floated on the surface of water.

The X-ray diffraction pattern of the resulting powder showed a strongpeak at a d value of 33.0 Å.

The atomic ratio of silicon to aluminum was found to be 14 as a resultof fluorescent X-ray spectrophotometry.

As a result of measuring the specific surface area and pore sizedistribution by the nitrogen adsorption and desorption method, it wasfound that the specific surface area was 920 m²/g and pore size was 2.2nm.

EXAMPLE 11

In the same manner as in Example 10, except for the use of 2.28 g oftetraethyl orthotitanate instead of aluminum isopropoxide, 55.6 g of drywhite powder was obtained. A 5 g portion of the white powder wasextracted in the same manner as in Example 2, whereby 3.4 g ofmethyl-containing silica.titania mesopore molecular sieve was obtained.The resulting powder exhibited water repellency and when added to water,it floated on the surface of the water.

The X-ray diffraction pattern of the resulting powder showed a strongpeak at a d value of 32.5 Å.

The atomic ratio of silicon to titanium was found to be 65 as a resultof fluorescent X-ray spectrophotometry.

As a result of measuring the specific surface area and pore sizedistribution by the nitrogen adsorption and desorption method, it wasfound that the specific surface area was 1100 m²/g and pore size was 2.2nm.

EXAMPLE 12

In the same manner as in Example 2, except for the use of 8.4 g of3-trifluoropropyltrimethoxysilane instead of methyltriethoxysilane, 19.g of a dried product was obtained. A 10 g portion of the product wasextracted in the same manner as in Example 2, whereby 6.5 g of whitepowder was obtained. The resulting powder exhibited water repellency andwhen added to water, it floated on the surface of the water.

The X-ray diffraction pattern of the resulting powder showed a strongpeak at a d value of 32.1 Å.

As a result of measuring the specific surface area and pore sizedistribution by the nitrogen adsorption and desorption method, it wasfound that the specific surface area was 1100 m²/g and pore size was 2.3nm.

As a result of measuring infrared absorption spectrum, absorption peaksattributable to a CF₃ group were observed at around 1320 cm⁻¹, 1269 cm⁻¹and 1218 cm⁻¹.

EXAMPLE 13

In the same manner as in Example 2, except for the use of 9.6 g of3-chloropropyltriethoxysilane instead of methyltriethoxysilane, 20 g ofa dried sample was obtained. A 10 g portion of the sample was extractedin the same manner as in Example 2, whereby 7 g of white powder wasobtained. The resulting powder exhibited water repellency and when addedto water, it floated on the surface of the water.

The X-ray diffraction pattern of the resulting powder showed a strongpeak at a d value of 34.6 Å.

As a result of measuring the specific surface area and pore sizedistribution by the nitrogen adsorption and desorption method, it wasfound that the specific surface area was 900 m²/g and pore size was 2.3nm.

EXAMPLE 14

In the same manner as in Example 2, except that the amount of tetraethylorthosilicate was changed to 38 g and that 5.4 g of3-cyclopentadienylpropyltriethoxysilane (dimer) was used instead ofmethyltriethoxysilane, 18 g of a dried sample was obtained. A 10 gportion of the sample was extracted with alcohol in the same manner asin Example 1, whereby 6.9 g of white powder was obtained. The resultingpowder exhibited water repellency and when added to water, it floated onthe surface of the water.

The X-ray diffraction pattern of the resulting powder showed a strongpeak at a d value of 33 Å.

As a result of measuring the specific surface area and pore sizedistribution by the nitrogen adsorption and desorption method, it wasfound that the specific surface area was 850 m²/g and pore size was 2.0nm.

EXAMPLE 15

In the same manner as in Example 2, except for the use of 12 g ofdodecyltriethoxysilane instead of methyltriethoxysilane, 21 g of a driedsample was obtained. A 10 g portion of the sample was extracted withalcohol in the same manner as in Example 1, whereby 7.2 g of whitepowder was obtained. The resulting powder exhibited water repellency andwhen added to water, it floated on the surface of the water.

The X-ray diffraction pattern of the resulting powder showed a strongpeak at a d value of 39 Å.

As a result of measuring the specific surface area and pore sizedistribution by the nitrogen adsorption and desorption method, it wasfound that the specific surface area was 830 m²/g and pore size was 2.6nm.

EXAMPLE 16

In the same manner as in Example 2, except that 6 g of n-dodecane wasused together with dodecylamine for the synthesis, 18 g of a driedsample of a methyl-containing silica mesopore molecular sieve wasobtained. A 10 g portion of the sample was extracted with alcohol in thesame manner as in Example 1, whereby 6.2 g of white powder was obtained.The resulting powder exhibited water repellency and when added to water,it floated on the surface of the water.

The X-ray diffraction pattern of the resulting powder showed a strongpeak at a d value of 36 Å.

As a result of measuring the specific surface area and pore sizedistribution by the nitrogen adsorption and desorption method, it wasfound that the specific surface area was 860 m²/g and pore size was 3nm.

EXAMPLE 17

In the same manner as in Example 2, except for the use of 5.9 g ofdimethyldiethoxyeilane instead of methyltriethoxysilane, 15 g of a driedsample of a methyl-containing silica mesopore molecular sieve wasobtained. A 10 g portion of the sample was extracted with alcohol in thesame manner as in Example 1, whereby 7.2 g of white powder was obtained.The resulting powder exhibited water repellency and when added to water,it floated on the surface of the water.

The X-ray diffraction pattern of the resulting powder showed a strongpeak at a d value of 32.6 Å.

As a result of measuring the specific surface area and pore sizedistribution by the nitrogen adsorption and desorption method, it wasfound that the specific surface area was 1060 m²/g, pore volume was 0.76cc/g and pore size was 2.3 nm.

As a result of infrared absorption spectrum, an absorption peakattributable to a Si—CH₃ group was observed at around 1265 cm⁻¹.

EXAMPLE 18

In the same manner as in Example 2, except for the use of 9.4 g oftrimethylethoxysilane instead of methyltriethoxysilane for thesynthesis, 15 g of a dried sample of a methyl-containing silica mesoporemolecular sieve was obtained. A 10 g portion of the sample was extractedwith alcohol in the same manner as in Example 1, whereby 6.9 g of whitepowder was obtained. The resulting powder exhibited water repellency andwhen added to water, it floated on the surface of the water.

The X-ray diffraction pattern of the resulting powder showed a strongpeak at a d value of 33.4 Å.

As a result of measuring the specific surface area and pore sizedistribution by the nitrogen adsorption and desorption method, it wasfound that the specific surface area was 900 m²/g, pore volume was 0.65cc/g and pore size was 2.2 nm.

As a result of infrared absorption spectrum, an absorption peakattributable to a Si—CH₃ group was observed at around 1255 cm⁻¹.

EXAMPLE 19

In the same manner as in Example 2, except that 16.5 g ofoctylchlorosilane was used instead of methyltriethoxysilane and aqueousammonia was added to adjust pH to 10, 14.5 g of a dried sample of aoctyldimethyloilyl-containing silica mesopore molecular sieve wasobtained. A 10 g portion of the sample was extracted with alcohol in thesame manner as in Example 1, whereby 7.9 g of white powder was obtained.The resulting powder exhibited water repellency and when added to water,it floated on the surface of the water.

The X-ray diffraction pattern of the resulting powder showed a strongpeak at a d value of 41.9 Å.

As a result of measuring the specific surface area and pore sizedistribution by the nitrogen adsorption and desorption method, it wasfound that the specific surface area was 800 m²/g, pore volume was 0.76cc/g and pore size was 2.4 nm.

As a result of infrared absorption spectrum, an absorption peakattributable to a Si—CH₃ group was observed at around 1257 cm⁻¹.

EXAMPLE 20

In a 500-ml beaker, 4.8 g of polyoxyethylene (polymerization degree: 10)octylphenyl ether were added to 300 g of distilled water to dissolve theformer in the latter. Under stirring, 7.3 g of tetraethyl orthosilicate,12 g of tetramethyl orthosilicate and 6.5 g of methyltriethoxysilanewere added. The resulting mixture was reacted under stirring by astirrer at room temperature for 2.5 days. The reaction mixture wasfiltered, washed with water and then dried at 110° C. for 5 hours,whereby 12.4 g of a dried product was obtained as white powder. In orderto remove the template (amine) from the dried product to obtain amesopore substance, a 5 g portion of the dried product was dispersed in750 ml of ethanol and extracted therewith at 60° C. for one hour,followed by filtration. This extraction and filtration procedure wasrepeated and carried out three times in total. The filtrate was thenwashed with alcohol and dried at 100° C. for 3 hours, whereby 3.2 g of amethyl-containing silica mesopore molecular sieve was obtained. Theresulting powder exhibited water repellency and when added to water, itfloated on the surface of the water.

As a result of measuring the specific surface area and pore sizedistribution by the nitrogen adsorption and desorption method, it wasfound that the specific surface area was 880 m²/g and pore size was 2.5nm.

As a result of infrared absorption spectrum, an absorption peakattributable to the deformation vibration of a C₃—Si group was observedat around 1280 cm⁻¹.

As a result of differential thermal analysis (measured at a heating rateof 15° C./min in the air), weight reduction and exotherm peak were foundat around 640° C.

COMPARATIVE EXAMPLE 1

In the same manner as in Example 1, except that the amount of tetraethylorthosilicate was changed to 41.6 g and methyl triethoxysilane was notadded, the reaction was effected. The reaction mixture was filtered,washed with water and then dried at 110° C. for 5 hours, whereby 18.7 gof a dried product was obtained as white powder. In order to remove thetemplate (amine) from the dried product to obtain a mesopore substance,a 10 g portion of the dried product was dispersed in 1500 ml of ethanoland extracted therewith at 60° C. for one hour, followed by filtration.This extraction and filtration procedure was repeated twice, inaddition. The filtrate was then washed with alcohol and dried at 100° C.for 3 hours, whereby 6.5 g of a silica mesopore molecular sieve wasobtained. The resulting powder did not exhibit water repellency and whenadded to water, it sank under water.

The powder X-ray diffraction pattern exhibited a strong peak at a dvalue of 36.2 Å.

As a result of measuring the specific surface area and pore sizedistribution of the powder by the nitrogen adsorption and desorptionmethod, it was found that the specific surface area was 1000 m²/g andpore size was 3.1 nm.

As a result of infrared absorption spectrum, no absorption peakattributable to the deformation vibration of a CH₃—Si group wasobserved.

As a result of differential thermal analysis (measured at a heating rateof 15° C./min in the air), no exotherm peak was found at 400° C. orhigher.

COMPARATIVE EXAMPLE 2

In order to remove the template (amine) from the dried powdersynthesized in Comparative Example 1 and to obtain a mesopore substance,a 10 g portion of the dried product was calcined in the air at 250° C.for 2 hours and then at 550° C. for 3 hours, whereby 6.3 g of a mesoporesubstance was obtained. A 2 g portion of the resulting mesoporesubstance was dispersed in 20 g of trimethylsilyl chloride, as anordinarily-employed alkylsilylating agent, and 30 g ofhexamethyldisiloxane. Under stirring, the dispersion was treated for 20hours under a reflux condition. The reaction mixture was then filtered,washed with acetone and dried. The sample so treated exhibited waterrepellency.

As a result of differential thermal analysis (measured at a heating rateof 15° C./min in the air), an exotherm peak was found at 450° C.

COMPARATIVE EXAMPLE 3

In order to remove the template (amine) from the dried powdersynthesized in Comparative Example 1 and to obtain a mesopore substance,a 10 g portion of the dried product was calcined in the air at 250° C.for 2 hours and then at 550° C. for 3 hours, whereby 6.3 g of a silicamesopore substance was obtained. A 2 g portion of the resulting silicamesopore substance was filled in a quartz-made reaction tube and heatedto 150° C. The tube was then fed with 100 cc/min of nitrogen and 10 cc/hof a 50/50 (volume) mixed solution of methyltrimethoxysilane and benzenefor 2 hours. After completion of the feeding with the solution, onlynitrogen was fed at the same temperature for one hour. The sample sotreated was taken out after cooling.

As a result of differential thermal analysis (measured at a heating rateof 15° C./min in the air), an exotherm peak and weight reduction werefound at around 520° C.

COMPARATIVE EXAMPLE 4

In the same manner as in Example 10, except that methyltriethoxysilanewas not added and the amount of tetraethyl orthosilicate was changed to123 g, a silicas alumina mesopore substance was obtained. In order toremove the template (amine) from the dried powder so synthesized and toobtain a mesopore substance, a 10 g portion of the dried product wascalcined in the air at 250° C. for 2 hours and at 550° C. for 3 hours,whereby 6.4 g of a mesopore substance was obtained. A 5 g portion of theresulting mesopore substance was added to a solution of 3.6 g ofmethyltriethoxysilane in 50 ml of toluene, followed by silylationtreatment at 100° C. for 9 hours, The reaction mixture was thenfiltered, washed sufficiently with acetone and then subjected to vacuumdrying (at 150° C. and 1 mmHg for 3 hours), whereby 5.6 g of a treatedsample was obtained.

As a result of measuring the specific surface area, pore volume and poresize distribution by the nitrogen adsorption and desorption methodbefore and after the methylsilation, it was found that the specificsurface area decreased from 900 m²/g to 700 m²/g, the pore volume from0.7 to 0.5 cc/g and pore size from 3 nm to 2.5 nm.

The sample was dispersed in benzene and the acid amount was determinedby titration with a Dimethyl Yellow indicator (pKa=+3.3) in a 0.1 Nn-butylamine benzene solution. As a result, it was confirmed that theacid amount showed a drastic reduction from 0.34 mmol/g to 0.14 mmol/gThe acid amount of the sample, which had been synthesized in Example 10,was determined in the same manner as in the above-described method andwas found to be 0.33 mmol/g, which suggests that the acid amount is highin the sample obtained by the process of the present invention.

As a result of dif ferential thermal analysis (measured at a heatingrate of 15° C./min in the air), an exotherm peak and weight reductionwere found at around 520° C. The sample synthesized in Example 10 showedan exotherm peak at 570° C., higher than the above temperature.

When the above-described methylsilylated sample was calcined at 600° C.to remove the methyl group, the pore size showed an increasing tendencyfrom 2.5 nm to 2.6 nm. The sample synthesized in Example 10, on theother hand, showed a decreasing tendency from 2.2 nm to 2.0 nm even bythe same treatment and the behavior was therefore different.

COMPARATIVE EXAMPLE 5

From the silicae.alumina mesopore substance synthesized in the samemanner as in Comparative Example 4, the template (dodecylamine) wasremoved in the same manner as in Example 10 using ahydrochloric-acid-acidity alcohol solvent.

The resulting sample was trimethylsilylated in the same manner as inComparative Example 2 and thus treated sample was filtered, washedsufficiently with acetone and subjected to vacuum drying (at 150° C. and1 mmHg for 3 hours).

As a result of measuring the specific surface area, pore volume and poresize distribution before and after the methylsilylation by the nitrogenadsorption and desorption method, the specific surface area showed adecrease from 960 m²/g to 770 m²/g, the pore volume from 0.76 to 0.65cc/g and the pore size from 3.1 nm to 2.6 nm.

The sample was dispersed in benzene and the acid amount was determinedby titration with a Dimethyl Yellow indicator (pKa=+3.3) in a 0.1 Nn-butylamine benzene solution. As a result, it was confirmed that theacid amount showed a drastic reduction from 0.3 mmol/g to 0.17 mol/g.The acid amount of the sample, which had been synthesized in Example 10,was determined in the same manner as in the above-described method andwas found to be 0.33 mmol/g, which suggests that the acid amount is highin the sample obtained by the process of the present invention.

When the above-described methylsilylated sample was calcined at 600° C.to remove the methyl group, the pore size showed an increasing tendencyfrom 2.6 nm to 2.7 nm. The sample synthesized in Example 10 on the otherhand, showed a decreasing tendency from 2.2 nm to 2.0 nm even by thesame treatment and the behavior was therefore different.

Industrial Applicability

The present invention provides a novel mesopore molecular sieve having ahydrocarbon group bonded directly to a silicon atom constituting theskeleton and production process thereof. According to the process of thepresent invention, it is possible to easily synthesize a novel mesoporemolecular sieve having a carbon-silicon bond while controlling itscontent in a wide range. The mesopore molecular sieve of the presentinvention is superior in a catalytic performance as an acid catalyst oroxidation catalyst as compared to those having a hydrocarbon-containingsilicon introduced therein by the conventional modification treatment.

What is claimed is:
 1. A mesopore molecular sieve having an oxide skeleton and a hydrocarbon group bonded directly to a silicon atom on the oxide skeleton constituting the molecular sieve, wherein the content of said hydrocarbon group is from 0.01 to 0.6 mol per mol of the metal oxide.
 2. The mesopore molecular sieve according to claim 1, wherein the hydrogen group is a C₁₋₁₆ hydrocarbon group or a hydrocarbon group substituted with an N-, O-, S-, P- or halogen-containing group.
 3. The mesopore molecular sieve according to claim 1 or 2, wherein the oxide is a silicon oxide.
 4. The mesopore molecular sieve according to claim 1 or 2, wherein the oxide is a composite of silicon oxide and at least one oxide selected from aluminum oxide, boron oxide or titanium oxide.
 5. A process for producing a mesopore molecular sieve having and a hydrocarbon group bonded to a silicon atom in the molecular sieve skeleton, which comprises synthesizing the mesopore molecular sieve, in the presence of a template, from: silane compound represented by the following formula (1): R_(n)SiX_((4−n))  (1)  wherein R represents a hydrocarbon group selected from C₁₋₁₆ hydrocarbon groups and hydrocarbon groups substituted with an N-, O-, S-, P- halogen-containing group; n represents 1, 2 or 3; and X is selected from C₁₋₁₆ alkoxy groups, aryloxy groups, a hydroxyl group and halogen atoms and a plurality of X may be the same or different; and a metal oxide and/or a precursor thereof.
 6. The process according to claim 5, wherein the silane compound is represented by the following formula (2):

wherein R represent a hydrocarbon group selected from C₁₋₁₆ hydrocarbon groups substituted with an N-, S-, O-, P- or halogen-containing group; X¹, X² and X³ each is selected from C₁₋₁₆ alkoxy groups, aryloxy groups, a hydroxyl group and halogen atoms.
 7. The process according to claim 5, wherein the oxide is a silicon oxide.
 8. The process according to claim 5, wherein the oxide is a composite of silicon and at least one oxide selected from aluminum oxide, boron oxide or titanium oxide.
 9. The process according to claim 5, wherein the silane compound is a monoalkyltrialkoxysilane or monoaryltrialkoxysilane. 